It is common practice for underwater divers, explorers and swimmers to wear a closely fitting, waterproof, protective suit made of relatively heavy and relatively nonelastic neoprene, rubber, vinyl, styrene or other like material. These suits conform closely to the body contours of the wearer leaving a thin air film between the skin and the suit which protects the wearer from cold in deep dives, or icy waters.
Conventional wet suits have certain disadvantages, foremost of which is their tendancy to quickly drain the wearer of energy. This is because they are relatively inelastic and cling closely to the body requiring considerable effort to move the arms and legs in swimming and walking under water. Because of their tightness, wet suits are difficult to put on and take off, and if the wearer gains weight this difficulty is increased to the point, in some instances, where the suit will no longer stretch to accommodate the wearer.